Method of getting up steam in steam-boilers



(No Model.)

W. CRAIG.

METHOD OF GETTING UP STEAM IN STEAM BOILERS.

Patented Oct. 6, 1885.

N. PETERS. PMlol-khagmhen Wnh ngton. D. C-

UNITED STATES PATENT OFFICE,

\VILLIAM CRAIG, OF BROOKLYN, NEW YORK.

METHOD OF GETTING UP STEAM IN STEAM-BOILERS.

SSE'ECIPICATION forming part of Letters Patent No. 327.659, datedOctober 6, 1885.

Serial No. 140,240. (No model.)

To all whom it may concern:

Be it known that I, W ILLIAM CRAIG, of the city of Brooklyn, in thecounty of Kings and State of New York, have invented a new and usefulMethod of Getting up Steam in Steam- Boilers, of which the following isa specification.

Modern marine boilers, more especially those of large size, aresubjected to enormous strains in getting up steam,by reason of theunequal expansion due to the wide variationsin the temperature of thewater in different parts of the boiler. In some marine boilers, if steamis got up quickly, it will be found that thetemperature in the upperpart of the boiler may be over 320 Fahrenheit, while at the bottom ofthe boiler it may be as low as 50. The difierences in expansion commenceas soon as the temperature in those parts of the boiler which are mostexposed to or affected by the heat of the furnace begins to rise, whichis very soon after the fires are lighted, and continues many hours afterthe fires are lighted.

The object of my invention is to inaugurate a new system of getting upsteam in a steamboiler, whereby the water may be raised to a hightemperature which is uniform or nearly uniform throughout the boilersbefore fires are lighted in the furnace. By this system of heating thewater both the extent or degree and duration of the strain produced byunequal expansion will be reduced to a minimum.

The invention includes a method of getting up steam in a main boiler,consisting in first getting up steam in another or supplemental boiler,in then simultaneously circulating and heating the water in the mainboiler before the fires are lighted in the furnaces thereof by aninjecting current of steam from the other or supplemental boiler, and instarting the fires in the furnaces of the main boiler after the watertherein has become so uniformly heated by steam from the other orsupplemental boiler as to greatly lessen the liability of strain due tounequal expansion by the heat of the fires in said furnaces.

The invention also includes a method of getting up steam in a mainboiler, consisting in first getting up steam in another or supplementalboiler, in then simultaneously circulat boiler, and in starting thefires in the furnaces of the main boiler after the water has become souniformly heated by steam from the other or supplementa boiler as togreatly lessen the liability of strain due to unequal expansion by theheat of the fires in the said furnaces.

By the method above described the water in a main marine boiler may beuniformly heated to a temperature of 210 Fahrenheit (more or less) bymeans of steam taken from the donkey or supplemental boiler, and beforethe fires are lighted in the main boiler, and when there are a number ofmain boilers the water in one of them may be thus heated with steam fromthe donkey-boiler before fires are lighted, and the steam generated inthat main boiler alter the fires are lighted may be employed to heat thewater in the other main boilers.

By this method of heat-ing the water in the main boiler or boilers notonly will the injurious effects of unequal expansion be greatlylessened, but a considerable saving of fuel will be made over theordinary method of heating the water in a boiler by fires in thefurnaces thereof preparatory to making steam.

In carrying out my new method I may employ any of the means heretoforeused for circulating the water in a steam-boiler after the fires arelighted in the furnaces thereof; but I now deem it desirable to employan injecting device arranged external to the main boiler, as shown in myUnited States Letters Patent No. 294,118, dated February 26, 188i, thesuction-pipe of the injector or injecting device leading from the loweror one part of the boiler and the discharge-pipe of the injector orinjecting device leading to the upper orvention, also showing in dottedlines an arbitrary illustration of a donkey-boiler; and Fig.

ioo

provided with a valve, D

illustrated; but the boiler may be constructed in any ordinary orapproved manner.

I have represented the injecting device or injector B at the back of theboiler; but it may be arranged at the front or any other desired partthereof, and each boiler should be provided with an injecting device orinjector for producing a circulation of the water therein.

The injecting device or injector may be of any well-known or suitabletype, and is provided with supply and discharge pipes G D, whereby it isconnected with different parts of the boiler. As here sh0wn,thesupply-pipe 0 leads from a point very near the bottom of the boiler tothe water-inlet of the injector B, and the discharge-pipe D leads fromthe in jector to the upper part of the boiler, and may enterthe boilerat a point near the water-line.

Steam is supplied to the injector B through a pipe, E. in, which is avalve, E, and communication of the supply and delivery pipes with theboiler is controlled by valves G D. The injector may also be providedwith the usual overflow, S.

The supply-pipe O has a branch, 0 extending below its point ofconnection with the boiler, and provided with a valve, 0 From thedischarge-pipe leads a branch pipe, D The branches 0 D, with theirvalves, serve a purpose hereinai'terdescribed.

As here represented,the steam-supply pipe E is connected with thesteam-space of the boiler A, and from it extends a branch steampipe, E*,which I have shown partly in dotted lines, and which leads from anarbitrary representation of a donkey boiler, F, also shown in dottedlines. In the branch steampipe is a valve, (1, and in the main steampipeE, between the branch pipe and the boiler A, is a valve, E".

Vhen the time has arrived for heating the 'water in the boiler A, andbefore the fires are lighted therein, the valves 0 D are opened to placethe injector in communication with the water in the boiler, and thevalves E a are then opened to admit steam from the donkeyboiler to theinjector. By the current of steam thus passed through the injector thewater is taken from the bottom of the boiler A, heated, anddeliveredinto the top thereof, and the impelling current of steambecoming mingled with and condensed by the water imparts heat thereto,thereby heating and circulating the water simultaneously. A

It will be understood that this heating of the water in the boiler A isperformed before the fires in the furnaces thereof are lighted, and theheating is continued until the water has a nearly-uniform temperaturethrough- .out, and is almost or quite hot enough to generate vapor. Ahas thus been uniformly heated by the mingling of steam with it,thefires in the furnaces are lighted, and the circulation of water by theinjector may be continued with steam from the donkey-boiler F untilsteam is generated in the main boiler, and may be thereafter con- Whenthe water in the boiler tinned with steam from the boiler A, the valveabeiug closed and thevalve E opened. When this method is carried out,the water in the boiler is thus heated uniformly, or nearly so,throughout before the fires therein are lighted, and the evil effects ofunequal expansion are to a great extent obviated, and not only is thismost desirable result attained, but less coal will be used than isrequired when the preliminary heating of the water is by fires in thefurnaces.

When there are two or more main boi1ers,the water in one of them may bethus heated by steam from the donkey-boiler before the fires are lightedin the furnaces, and after steam is generated in that main boiler byfires in the furnaces the water in the other boiler or boilers may bethus heated by steam from the first main boiler.

It is obvious that to secure a uniform heating of the water in theboilerA the water may with advantage be drawn through the supplypipe 0from different points along the length of the boiler, and may be widelydistributed from the deliveryor discharge pipe D. To provide for this,the said supply and discharge pipes O D may have perforatedprolongations 0* D extending within the boiler, as shown in Fig. 2.These prolongations may be eX- tended nearly the entire length of theboiler, if desired, and should be closed at the ends to compel the waterto pass through the perforations.

It may be desired to use the injeeting'device B for discharging thewater from the boiler A when steam is off. In such case it is onlynecessary to close the valve D in the discharge-pipe D and open thevalve D in the branch pipe D The water taken from the bottom of theboiler may then be discharged overboard by steam from the donkey-boiler.

It may also be desirable to employ the injector to dischargebilge-water, and if so the valve D is still left open, and the valve 0in the branch suction or supply pipe 0 is also opened, the valve 0 beingclosed. When each of the main boilers of a vessel is provided with aninjector thus arranged, they may all be operated by steam from theirrespective performed deliver water into the upper part of the boiler,they might be otherwise arranged to take water from any part of theboiler and deliver it to another part thereof, as may be most de'sirable.

The holes in the pipes that extend throughout the top and bottom of theboiler should be laid out differentiallythat is to say, a small numberin the first twelve inches of their length and increasing in numbers asto their lengthfor the purpose of drawing and discharging the wateruniformly throughout the length of the boiler.

I am aware that to enable steam to be generated in a locomotive morerapidly than heretofore after the fires are lighted it has been proposedto introduce steam from another or supplemental boiler simultaneouslyinto the steam space or dome and flue or smoke stack of the locomotive.The steam which is introduced into the steam space or dome serves toheat the water and the steam which is introduced into the flue orsmoke-stack serves to create a draft, which promotes combustion in thefurnace of the locomotive.

I am also aware that to promote the draft when fires are first lightedin locomotives, and to facilitate the heating of the water therein, ithas been proposed to discharge steam from a supplemental boilersimultaneously into the smokestack and waterspace of a locomotive. Thepurpose of discharging steam into the smoke-stack is to promote a draftin the locomotive while stationary, and just after starting a fire inthe furnace thereof, and the purpose of introducing steam into thewater-space of the locomotive is to heat the water on the inside of theboiler-plates at the same time they are heated on the outside by thefurnace-fire.

In both the above-described methods no steam is discharged into thelocomotive-boiler until after the fires are lighted therein, and in thisrespect both said methods differ from that pursued by me. In carryingout my improved method I produce by an injecting current of steam fromasupplemental boiler a rapid circulation of the water in the main boilerbefore the fires are lighted in the furnace thereof, and I do not lightsaid fires until all the water in the main boiler has been brought to auniformly highly-heated state by the circulation produced by theinjecting current of steam from the supplemental boiler.

I do not desire to include in my invention any method which involves thelighting of the fires in the furnace of the main boiler first and theinjecting of steam into the water of the main boiler afterward.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. The herein-described method of getting up steam in a steam-boiler,consisting in first getting up steam in another or supplemental boiler,in then simultaneously circulating and heating the water in the mainboiler before the fires are lighted in the furnaces thereof by aninjecting current of steam from the other or supplemental boiler, and instarting the fires in the furnaces of the main boiler after the watertherein has become so uniformly heated by steam from the other orsupplemental boiler as to greatly lessen the liability of strain due tounequal expansion by the heat of the fires in said furnaces,substantially as herein set forth.

2. The herein-described method of getting up steam in a main boiler,consisting in first getting up steam in another or supplemental boiler,in then simultaneously circulating and heating the water in the mainboiler before the fires are lighted in the furnaces thereof by aninjecting current of steam from the other or supplemental boiler,whereby water is drawn from one part of the main boiler,heated, anddischarged into another part thereof, and in starting the fires in thefurnaces of the main boiler after the water therein has become souniformly heated by steam from the other or supplemental boiler as togreatly lessen the liability of strain due to unequal expansion by theheat of the fires in said furnaces, substantially as herein set forth.

WILLIAM CRAIG.

\Vitnesses:

O. HALL, FREDK. HAYNES.

